When artist and writer Maurice Sendak died Tuesday morning at the age of 83, he left behind a massive body of work, stretching back more than half a century. His most famous book, Where the Wild Things Are, sold nearly 20 million copies. But Sendak’s greatest legacy was his philosophy on childhood, and on life.

In Sendak’s world, childhood was beautiful, but it could also be scary, confusing and sometimes horrible. He had little time for sanitized cuteness and lighthearted naiveté.

“As a parent, I read Where the Wild Things Are to my children,” said The Graveyard Book author Neil Gaiman in an e-mail exchange with Wired. “But [my daughter] Holly’s favorite was Outside, Over There, and I must have read it to her hundreds of times, perhaps thousands of times, marveling at Sendak’s economy of words, his cruelty, his art.”

For Sendak, who was born in Brooklyn in 1928, childhood was often terrifying — marred by frequent illness and vivid memories of the Great Depression and World War II. The wily, raucous creatures in Where the Wild Things Are, according to many accounts, were patterned after Sendak’s Brooklyn relatives.

“What I loved,” Gaiman said, “what I always responded to, was the feeling that Sendak owed nothing to anyone in the books that he made. His only obligation was to the book, to make it true. His lines could be cute, but there was an honesty that transcended the cuteness.”

Sendak illustrated (and often wrote) dozens of memorable children’s books over the course of a storied career. But he hated being called a children’s book illustrator, despite winning several accolades for illustration, including the Caldecott Medal, the top prize in children’s book illustration, which he received in 1964. In a 1966 interview with Nat Hentoff in The New Yorker, Sendak argued, “I really do these books for myself. It’s something I have to do, and it’s the only thing I want to do. Reaching the kids is important, but secondary. First, always, I have to reach and keep hold of the child in me.”

Sendak had a rough, plain-spoken manner and a dark sense of humor. In an interview with The Guardian in 2011, he lambasted the late, beloved children’s book author Roald Dahl. “The cruelty in his books is off-putting,” Sendak said. “Scary guy. I know he’s very popular, but what’s nice about this guy?”

He had harsh words, too, for fairy-tale legend Hans Christian Andersen, in a 2006 profile in The New Yorker. “For me, he’s too morbid,” Sendak said. “Why did the little mermaid have to bleed? Why did the girl with the red shoes have to die?”

Sendak’s 1970 book In the Night Kitchen — in which a naked child nearly gets turned into a cake — was famously controversial, and is still the 24th-most-challenged library book of the past decade, according to the American Library Association’s list of frequently challenged books.

Gaiman recalled that In the Night Kitchen was his first Sendak book.

‘Too many parents and too many writers of children’s books don’t respect the fact that kids know a great deal and suffer a great deal.’

“I was 11 or 12, and had been given a small allowance by my parents to buy my littlest sister, who did not read, books, if I would read them to her,” Gaiman said. I loved books and reading aloud. It was liberating, transgressive and a dream come to life: I understood the nakedness, could not understand why all the chefs were Oliver Hardy but loved that all the chefs were Oliver Hardy. Years later I discovered Little Nemo in Slumberland, and In The Night Kitchen came into focus.”

When Sendak first began drawing for children’s books, editors told him that his illustrations weren’t pretty enough, or normal enough — that they were too strange, even ugly. His characters were rotund and freaky-looking, with spindly legs and odd features. But Sendak viewed his unique illustrations as expressionistic, representing children’s inner tumult, their mess of emotions.

“Too many parents and too many writers of children’s books don’t respect the fact that kids know a great deal and suffer a great deal,” Sendak told The New Yorker’s Hentoff. “It’s not that I don’t see the naturalistic beauty of a child. I’m very aware of that beauty, and I could draw it…. But I am trying to draw the way children feel — or rather, the way I imagine they feel. It’s the way I know I felt as a child.”

Sendak’s great gift for being able to “draw the way children feel” gave his work universal appeal. His memorable creatures — like Max, the little boy in the wolf suit who conquers the monsters to become the “king of the wild things” in Where the Wild Things Are, were something every child could relate to and understand. For children — and for many adults, too — Sendak was, and still is, their hero.

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